MITOSIS. What is the cell cycle?. Growth And Division. What is Mitosis?. Nuclear Division. What is Chromatin ?. ( Thin Chroma tin ) Stretched out, unwound DNA Looks like spaghetti Not visible under microscope. What is a Chromosome?.
Stretched out, unwound DNA
Looks like spaghetti
Not visible under microscope
Coiled up (condensed) version of chromatin; easier for moving DNA
(Looks like a slinky)
How many pairs of chromosomes do normal human cells have?
What is the Centromere?
Holds Sister Chromatids together
Where spindle fibers grab chromosome
(Think: Centro = center mere = middle)
Two identical strands of a chromosome
Name the phases of the
When cell gets bigger and makes lots of proteins
1st part of Interphase
Makes a copy of the DNA
Single strand →Double strand
2nd part of Interphase
What happens in the G2 Phase?
“Growth 2” Phase
Cell is getting ready to divide
Getting organelles and proteins
(Like going to grocery store to get the food to prepare dinner)
3rd part of Interphase
What happens in the M Phase?
Mitosis and Cytokinesis
What is the“Cell Growth and Protein Synthesis” stage that is the
longest phase of the Cell Cycle?
(NOT part of Mitosis)
Includes: G1, S, G2
Name the phases of Mitosis(Nuclear division)
“The Professional MetAna on the Telophone.”
What happens in Prophase?
Longest phase of Mitosis!!!
Spindle fibers (muscles of chromosome) form to help move
What happens in Metaphase?
Chromosomes are lined up in the middle of the cell
Spindle fibers are attached and centrioles go to the poles
What happens in Anaphase?
Chromosomes get pulled apart by spindle fibers
What happens in Telophase?
“The End” or “Tidy Up”
Uncoiling of chromosomes
Nuclear envelope reforms
Spindle fibers go “bye-bye”
This is the next stage after mitosis.
Actual cell division into two cells dividing into two daughter cells
What structure appears?
Cytokenesis in Plant Cells
What structure appears?
Creates a CELL PLATE
(Think: Hard cell wall is like a hard plate)
What are the twonew identical cells made in cell division called?
Why do normal cells stop growing when they touch other cells or reach the sides of a petri dish?
Contact with other cells or the sides of the dish signal to the cell to stop growing.
This happens when you cut your finger. The cells grow rapidly to fill in the cut. When the cells touch, they go back to normal cell cycle.
What signals a cell to start the cell cycle? or reach the sides of a
What are internal regulators and external regulators? or reach the sides of a
Internal regulators are proteins that respond to events inside the cell .
External regulators are proteins that respond to events outside the cell.
What is it called when cells have lost their ability to control their growth?
What is it called when a cell grows and becomes control their growth?specialized?
What are stem cells? control their growth?
Cells that have not differentiated yet.
When a cell becomes larger, which increases faster: control their growth?
Volume or Surface Area?
The bigger the cell gets the less efficient the cell is at doing its job (function) in the body.
What are control their growth?diploid cells?
What are haploid cells?
2 pairs of chromosomes
Somatic Cells = 23 pairs
1 set of chromosomes
Sex Cells = 23 single chromosomes